Effect of natural colorants on color and antioxidant activity of “kolang kaling” (Sugar palm fruit) jam

Abstract

Background: The colors of Asian melastome fruit, Java plum rind and Mangosteen rind range from red to dark purple. These fruits are also rich in anthocyanins, making them useful as natural colorants. Materials and Methods: In this study, it was evaluated that the color and antioxidant activity of jams produced with different concentrations of juice extracted from these fruits. The juice extracts were added at concentrations of 6, 8, 10 and 12% during the production of sugar palm fruit jam. Results: Analysis of sugar palm fruit jam with added juice from Asian melastome fruits, Java plum rinds and Mangosteen rinds produced colors with0hue values of 6.90-14.00, 1.43-12.87 and 20.97-32.33, respectively and anthocyanin levels of 3.50-8.57, 3.28-11.19 and 1.61-3.73 mg L_1, respectively, the total phenol levels of 1.20-1.60, 1.32-1.94 and 0.83-3.51%, respectively. The antioxidant activity for each treatment exceeded 5,000 ppm, indicating a lack of activity. Conclusion: These results show that the addition of different amounts of natural colorants significantly affected the color of sugar palm fruit jam, as well as the total phenol and anthocyanin levels but did not improve antioxidant activity.